The one on my 75 Express fly bridge is a 3/4" tapered shaft, prior owner said he bought it off eBay, not sure if the helm is original though. Steering is the next project, after the engines, keep us posted.

Metalhead --- I have one that is close to the picture you posted. Mine came off of my 28 Express and looks like it will take a 3/4 inch tapered shaft. If you or anyone else is interested in it PM or email me. Jim B.